1. Field of the Invention
This invention relates to drier appliances and in particular to timer-controlled control means for use in drier appliances.
2. Description of the Prior Art
In Alvin J. Elders U.S. Pat. No. 3,597,139, owned by the assignee hereof, an improved dual coil gas burner control circuit is shown for use in a clothes drier or the like. The gas burners are fed from gas valves having electrical coil components connected in a circuit to be controlled by a timer-operated switch.
In U.S. Pat. No. 3,874,089 of Carl R. Offutt, which patent is also owned by the assignee hereof, a clothes drier control circuit is shown having a variable resistance connected in series with the timer motor of the drier control circuit. The variable resistance changes in response to heating to control the energization of the timer motor.
In U.S. Pat. No. 2,717,455 of John L. Harris et al, a drier control system is shown having means controlled conjointly by a timing means of the apparatus and thermostatic means thereof for preventing operation of the timing means until the thermostatic means reaches a "cold" position to permit operation of the heating means and then reaches a "hot" position to prevent operation thereof.
Robert L. Dunkelman, in U.S. Pat. No. 2,851,789, shows a control system for clothes dryers including a motor-driven timer, a heater cycling thermostat responsive to the temperature of inlet air entering the tumbling means from the heater and a second thermostat responsive to the temperature of the exhaust air leaving the tumbling means. The control is arranged to provide selectively continuous energization of the timer to provide a timed drying and tumbling operation. Alternatively, the timer may be controlled by the thermostat to provide a temperature-controlled operation.
Arthur Berendbaum, in U.S. Pat. No. 3,044,181, shows a heater control in a laundry apparatus wherein high heat is applied when the clothes are wet and lesser heat is applied as the moisture content of the clothes decreases.
In U.S. Pat. No. 3,254,421 of Elwood W. Kielsmeier et al., a method and apparatus for rapidly drying a sample of moist material is provided having a high heat timer and a total cycle timer. A capacitor is provided in the lead extending from a heating element to the high heat timer and to a variable voltage transformer.
Phillip L. Schmidgall, in U.S. Pat. No. 3,707,776, shows a control means for an inductance means wherein a resonant control means causes the voltage and current of an inductance drive means to be out of phase with each other so as to prevent operation of the inductance drive means. The electrical circuit is arranged so that an on-off operation of the inductance defined by the synchronous motor is effected by a resonant means which, when energized, causes the voltage-phase relationship of the inductance means to be out of phase so that the inductance means does not operate. The sensing means may be connected to a suitable appliance, such as an automatic clothes drier, to automatically control the on-off operation thereof.
In U.S. Pat. No. 3,806,308 of James R. Cahoe et al., a timer control circuit for a gas dryer is shown wherein operation of the timer may be dependent upon the condition of a solenoid-operated controlling valve assembly. In the summary portion of that patent it is stated that the timer control utilizes an ignition system of a gas burner to control timer run time to terminate a drying cycle. According to the disclosure of that patent the timer will run continuously throughout an automatic cycle except during periods when a control thermostat is closed and a radiant energy heat sensor switch is open.